The influences of different substituents on spectral properties of rhodamine B based chemosensors for mercury ion and application in EC109 cells

Abstract

Six rhodamine-based “turn-on” fluorescence chemosensors (L 1 –L 6 ) with different substituents for mercury (Hg 2+ ) were readily synthesized and investigated; they displayed high selectivity and chelation enhanced ratiometric fluorescence change and colorimetric change with Hg 2+ among the metal ions examined. Based on UV and fluorescence spectral data, the effects of different substituents on spectral properties of the probes were presented and discussed. The detection limit of Hg 2+ to probe L 1 was as low as 50 nmol/L because of its electron-donating group. Theoretical calculation also supported the process of reaction. Confocal laser scanning microscopy experiments showed that probe could be used to detect Hg 2+ in living cells.